SHM - Phase Changes

As part of my SHM lessons, I got this sheet today to study Phase Difference. I tried drawing what was asked and I have the impression I got the first two graphs correct. However, I am in doubt regarding the third, mostly I guess, with differentiating what is meant by ahead and behind

Thanks,
Peter G.

(The drawings are really sketches until I understand their shapes properly)

Yeah, that's what it asks for. So that means it starts like, an eighth of a cycle later? Do you think you could maybe draw a rough diagram on something like paint? I have a hard time conveying this kind of stuff in words

Staff: Mentor

Yeah, that's what it asks for. So that means it starts like, an eighth of a cycle later?

The diagram would look pretty much like what you drew. It starts an eighth of a cycle 'before' the first diagram. Interpret that like this: At t = 0 the top diagram is already at the peak, while the last diagram takes an eighth of a cycle before it gets to the peak. It's behind the other.